Electric signal



April 29 1924.

C. T. SCHIRMER ELECTRIC SIGNAL Filed Jan. 5, 1922 witness:

Fatented Apre 29, 1924.,

PATENT OFFICE.

CYRUS T. SCHIRMER, OF NEWTON,

CABOT ELECTRIC COMPANY, 01 MASSACHUSETTS.

ELECTRIC SIGNAL.

Application filed. Sanuary 5, 1922. Serial No. 527,177.

To all who 122,712? may concern:

Be it known that I, Cvuus T. SOHIRMER, a citizen of the United States, residing at Newton, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Electric Signals; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it ape pertains to make and use the same.

The present invention relates to an improvement in electric signals. I

The object of the invention is to produce a construction which, while adapted to make an audible signal by the use of a direct current, is also adapted for use with alternating current, to which it is more especially adapted.

In electric. signals used with alternating current there is a liability, owing to the alternations of the current, to chattering of the moving signal giving element, and one of the objects of this invention is to overcome this chattering. Another object of the invention is to reorganize and improve, as well as to simplify and reduce the cost of electric signals.

The accompanying drawing illustrates an elevation of the preferred form of the de vice.

The preferred form of the invention is described as follows: The device is applied with a base 10, to which an electro-magnet 11 is secured. The pole piece 12 of the magnet is projected beyond the end of the spool,

and is cut away at 1,3 for the purpose of localizlng the lines of force of the magnet. A nonmagnetic metal stop 14; is provlded,

which is secured by a screw to the end of the pole piece 12. A tapper 15, pivoted at 16, is normally held in raised position by a spring 17. The tapper i5 is made of soft iron, and the sto 14, is so located that the tapper is above the end of the pole piece in its normal or unenergized condition, When current is sent through the electro-magnet coil 11, it energizes the pole piece 12, which attracts the tapper to it. The tapper is made heavy enough either by its own bulk or by an additional weight 18 secured to it, so that the momentum-which it acquires in moving towardthe end of the pole piece is suflicient to carry it by that pole piece far enough so that the non-magnetic button 19 t on the lower surface of the end of the tapper strikes the fiat surface 20 of the pole piece, making an audible blow. So long as the coil 11 is energized, the tapper will-then be held opposite the end 21 of the pole piece, s

The gist of the invention consists in ar-- ranging the tapper so that the attraction of the magnetic field created in the pole piece will set it in motion, and cause it to move not only to the point of greatest attraction, but by its momentum carry it beyond that point, so that it will strike a blow upon a part adapted to receive it. Thus any chat tering of the tapper due to the reversals of current in the coil, if an alternating current is used, will be avoided.

Having thus described the invention, what is claimed is:

An electric signal having, in combination, a base, an electro-magnet provided with a spool and mounted on the base having a pole piece projected beyond the end oi. the spool and cut away to laterally localize the lines -of force of the magnet, a non-magnetic stop secured to the end of the pole piece, a pivoted tapper, a spring normally holdingthe tapper in raised position against the stop above the endvof the pole piece. said tapper being provided with anon-magnetic button adapted when the magnet is energized to strike a portion of the pole piece to make an audible blow.

CYRUS T. scninnnn. 

